Centre for Urban Environmental Remediation, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China.
Beijing Energy Conservation & Sustainable Urban and Rural Development Provincial and Ministry Co-construction Collaboration Innovation Center, Beijing University of Civil Engineering and Architecture, 100044, Beijing, China.
Environ Sci Pollut Res Int. 2023 Apr;30(17):50125-50133. doi: 10.1007/s11356-023-25862-4. Epub 2023 Feb 15.
Zhalong wetland is the largest inland saline wetland in Asia and susceptible to imbalance and frequent flooding during the freeze-thaw period. Changes in water level and temperature can alter the rate of greenhouse gas release from wetlands and have the potential to alter Earth's carbon budget. However, there are few reports on how water level, temperature, and their interactions affect greenhouse gas flux in inland saline wetland during the freeze-thaw period. This study revealed the characteristics of CO and CH fluxes in Zhalong saline wetlands at different water levels during the autumn freeze-thaw period and clarifies the response of CO and CH fluxes to water levels. The significance analysis of cumulative CO fluxes at different water levels showed that water levels did not have a significant effect on cumulative CO release fluxes from wetlands. Water levels, temperature, soil moisture content, soil nitrate, and ammonium nitrogen content and organic carbon content could explain 24.5-98.9% of CO and CH flux variation. There were significant differences in the average and cumulative CH fluxes at different water levels. The higher the water levels, the higher the CH fluxes. In short, water level had a significant effect on wetland methane fluxes, but not on carbon dioxide fluxes.
扎龙湿地是亚洲最大的内陆咸水湿地，在冻融期容易失衡和频繁发生洪水。水位和温度的变化会改变湿地温室气体的释放速率，并有可能改变地球的碳预算。然而，关于水位、温度及其相互作用如何影响内陆咸水湿地在冻融期的温室气体通量的研究报告很少。本研究揭示了不同水位下扎龙盐沼湿地在秋季冻融期的 CO 和 CH 通量特征，并阐明了 CO 和 CH 通量对水位的响应。不同水位下累积 CO 通量的显著性分析表明，水位对湿地累积 CO 释放通量没有显著影响。水位、温度、土壤含水量、土壤硝酸盐和铵态氮含量以及有机碳含量可以解释 CO 和 CH 通量变化的 24.5-98.9%。不同水位下的平均和累积 CH 通量存在显著差异。水位越高，CH 通量越高。总之，水位对湿地甲烷通量有显著影响，但对二氧化碳通量没有影响。
